Real-World Analysis of Potential Pharmacokinetic and Pharmacodynamic Drug Interactions with Apixaban in Patients with Non-Valvular Atrial Fibrillation

Purpose: We conducted this study to assess the real-world prevalence, nature, predictors, and clinical necessity of apixaban pharmacokinetic (PK) and pharmacodynamic (PD) drug interactions in patients with non-valvular atrial fibrillation (NVAF) at a tertiary medical institution in Saudi Arabia.

Patients and methods: An observational retrospective cohort analysis was conducted in adult patients diagnosed with NVAF receiving apixaban for stroke prevention from the period of June 2015 to May 2019.

Results: Of the 1271 patients included in the analysis, 611 (48.1%) patients had potential PD- or PK-drug interactions with apixaban. Of those, 490 (38.6%) patients had potential PD drug-drug interactions (DDIs) and 121 (9.5%) patients had potential PK-DDIs. PD-DDIs with apixaban were mainly with antiplatelet therapy followed by non-steroidal anti-inflammatory drugs and antidepressants. PK-DDIs with apixaban were mainly with combined P-gp/CYP3A4 inhibitors or inducers. History of minor bleeding was positively correlated with PD-DDIs with apixaban, ß coefficient = 0.455 (OR 1.58; 95% CI 1.01-2.45); p<0.05. History of acute coronary syndrome was positively correlated with PD-DDIs with apixaban, ß coefficient = 0.515 (OR 1.60; 95% CI 1.36-1.99); p<0.05. History of heart failure was positively correlated with PK-DDIs with apixaban, ß coefficient = 0.459 (OR 1.58; 95% CI 1.07-2.35); p<0.05. Almost 15% of the included patients had no clinical indication to receive the potential interacting drug with apixaban and about 20% of them were assuming an inappropriate apixaban dose according to the product package insert.

Conclusion: Pharmacodynamics and pharmacokinetics interactions are common in more than half of the patients with NVAF receiving apixaban for stroke prevention in this real-world analysis. Some of these interacting medications are not indicated. Drug-drug interactions should always be considered and monitored with apixaban with a regular assessment of the need for any interacting medication.